From DXSpider version 1.48, major changes were introduced to the way node connections are treated. This is part of an ongoing process to remove problems with loops and to enable talk and other functions to propagate across the whole of the worldwide cluster network. In fact, in a Spider network, it would be useful, perhaps even necessary to have loops. This would give real resilience to the network, meaning that if a link dropped, the information flow would simply come in and go out via a different route. Of course, we do not have a complete network of Spider nodes, there are other programs out there. Some of these do not have any protection from loops. Certainly AK1A does not handle loops well at all. It is therefore necessary to have some form of protection for these nodes.
This is achieved by using filtering on a route basis. There is a default setting to help to protect the network, especially useful for new and inexperienced SysOps. The idea is simple. When Spider is started for the first time and a connection is made to or from another node, the default is to only send the nodes you already have that are in your own zone. For example, in the UK the default setting would be to send only UK nodes to any connection. This can be filtered further (down to a single node if needed) or expanded as required.
As mentioned in the introduction, a default setting exists. If this is all you want to use then that is fine, you have nothing else to do. However, if you want to make any alterations then you need to know a bit about filters.
It is possible to reset the default setting for node connections should you wish to do so, however this can be dangerous to the network unless you have some experience in how all this works.... be careful! It is also possible to change settings for one connection only. You can, therefore, have many different filters set dependent on the amount of node links you have.
I should at this stage give a little bit of background on filters. All the filters in Spider work in basically the same way. You can either accept or reject various options in order to create the filter rules you wish to achieve. Some filters are user settable, others can only be altered by the sysop. Route filtering can only be done by the sysop.
As discussed previously, a default setting exists that only sends nodes from your own zone. This can be overridden by using the default_node filter option like this ...
reject/route default_node <filter_option>
or
accept/route default_node <filter_option>
where filter_option is one of the following ...
call <prefixes>
call_dxcc <numbers>
call_itu <numbers>
call_zone <numbers>
origin <prefixes>
origin_dxcc <numbers>
origin_itu <numbers>
origin_zone <numbers>
Please be careful if you alter this setting, it will affect ALL your links!
Exactly the same rules apply for general route filtering. You would use either an accept filter or a reject filter like this ...
reject/route <node_call> <filter_option>
or
accept/route <node_call> <filter_option>
where filter_option is one of the following ...
call <prefixes>
call_dxcc <numbers>
call_itu <numbers>
call_zone <numbers>
origin <prefixes>
origin_dxcc <numbers>
origin_itu <numbers>
origin_zone <numbers>
Here are some examples of route filters ...
rej/route gb7djk call_zone 61,38 (everything except UK+EIRE nodes)
rej/route all (equiv to [very] restricted mode)
acc/route gb7djk call_zone 61,38 (send only UK+EIRE nodes)
acc/route gb7djk call gb7djk (equiv to SET/ISOLATE)
Upto v1.44 it was not possible for the user to set their own filters. From v1.45 though that has all changed. It is now possible to set filters for just about anything you wish. If you have just updated from an older version of DXSpider you will need to update your new filters. You do not need to do anything with your old filters, they will be renamed as you update.
There are 3 basic commands involved in setting and manipulating filters. These are accept, reject and clear. First we will look generally at filtering. There are a number of things you can filter in the DXSpider system. They all use the same general mechanism.
In general terms you can create a 'reject' or an 'accept' filter which can have up to 10 lines in it. You do this using, for example ...
accept/spots .....
reject/spots .....
where ..... are the specific commands for that type of filter. There are filters for spots, wwv, announce, wcy and (for sysops) connects. See each different accept or reject command reference for more details.
There is also a command to clear out one or more lines in a filter. They are ...
clear/spots 1
clear/spots all
There is clear/xxxx command for each type of filter.
and you can check that your filters have worked by the command ...
show/filter
For now we are going to use spots for the examples, but you can apply the same principles to all types of filter.
There are two main types of filter, accept or reject. You can use either to achieve the result you want dependent on your own preference and which is more simple to do. It is pointless writing 8 lines of reject filters when 1 accept filter would do the same thing! Each filter has 10 lines (of any length) which are tried in order. If a line matches then the action you have specified is taken (ie reject means ignore it and accept means take it)
If you specify reject filters, then any lines that arrive that match the filter will be dumped but all else will be accepted. If you use an accept filter, then ONLY the lines in the filter will be accepted and all else will be dumped. For example if you have a single line accept filter ...
accept/spots on vhf and (by_zone 14,15,16 or call_zone 14,15,16)
then you will ONLY get VHF spots from or to CQ zones 14, 15 and 16.
If you set a reject filter like this ...
reject/spots on hf/cw
Then you will get everything EXCEPT HF CW spots. You could make this single filter even more flexible. For example, if you are interested in IOTA and will work it even on CW even though normally you are not interested in CW, then you could say ...
reject/spots on hf/cw and not info iota
But in that case you might only be interested in iota and say:-
accept/spots not on hf/cw or info iota
which achieves exactly the same thing. You should choose one or the other until you are comfortable with the way it works. You can mix them if you wish (actually you can have an accept AND a reject on the same line) but don't attempt this until you are sure you know what you are doing!
You can arrange your filter lines into logical units, either for your own understanding or simply convenience. Here is an example ...
reject/spots 1 on hf/cw
reject/spots 2 on 50000/1400000 not (by_zone 14,15,16 or call_zone 14,15,16)
What this does is to ignore all HF CW spots and also rejects any spots on VHF which don't either originate or spot someone in Europe.
This is an example where you would use a line number (1 and 2 in this case), if you leave the digit out, the system assumes '1'. Digits '0'-'9' are available. This make it easier to see just what filters you have set. It also makes it more simple to remove individual filters, during a contest for example.
You will notice in the above example that the second line has brackets. Look at the line logically. You can see there are 2 separate sections to it. We are saying reject spots that are VHF or above APART from those in zones 14, 15 and 16 (either spotted there or originated there). If you did not have the brackets to separate the 2 sections, then Spider would read it logically from the front and see a different expression entirely ...
(on 50000/1400000 and by_zone 14,15,16) or call_zone 14,15,16
The simple way to remember this is, if you use OR - use brackets. Whilst we are here CASE is not important. 'And BY_Zone' is just the same as 'and by_zone'.
As mentioned earlier, setting several filters can be more flexible than simply setting one complex one. Doing it in this way means that if you want to alter your filter you can just redefine or remove one or more lines of it or one line. For example ...
reject/spots 1 on hf/ssb
would redefine our earlier example, or
clear/spots 1
To remove all the filter lines in the spot filter ...
clear/spots all
You can filter in several different ways. The options are listed in the various helpfiles for accept, reject and filter.
Sometimes all that is needed is a general rule for node connects. This can be done with a node_default filter. This rule will always be followed, even if the link is isolated, unless another filter is set specifically. Default rules can be set for nodes and users. They can be set for spots, announces, WWV and WCY. They can also be used for hops. An example might look like this ...
accept/spot node_default by_zone 14,15,16,20,33
set/hops node_default spot 50
This filter is for spots only, you could set others for announce, WWV and WCY. This filter would work for ALL nodes unless a specific filter is written to override it for a particular node. You can also set a user_default should you require. It is important to note that default filters should be considered to be "connected". By this I mean that should you override the default filter for spots, you need to add a rule for the hops for spots also.
Once you are happy with the results you get, you may like to experiment.
The previous example that filters hf/cw spots and accepts vhf/uhf spots from EU can be written with a mixed filter, for example ...
rej/spot on hf/cw
acc/spot on 0/30000
acc/spot 2 on 50000/1400000 and (by_zone 14,15,16 or call_zone 14,15,16)
Note that the first filter has not been specified with a number. This will automatically be assumed to be number 1. In this case, we have said reject all HF spots in the CW section of the bands but accept all others at HF. Also accept anything in VHF and above spotted in or by operators in the zones 14, 15 and 16. Each filter slot actually has a 'reject' slot and an 'accept' slot. The reject slot is executed BEFORE the accept slot.
It was mentioned earlier that after a reject test that doesn't match, the default for following tests is 'accept', the reverse is true for 'accept'. In the example what happens is that the reject is executed first, any non hf/cw spot is passed to the accept line, which lets through everything else on HF. The next filter line lets through just VHF/UHF spots from EU.
In /spider/data you will find a file called hop_table.pl. This is the file that controls your hop count settings. It has a set of default hops on the various PC frames and also a set for each node you want to alter the hops for. You may be happy with the default settings of course, but this powerful tool can help to protect and improve the network. The file will look something like this ...
#
# hop table construction
#
package DXProt;
# default hopcount to use
$def_hopcount = 5;
# some variable hop counts based on message type
%hopcount =
(
11 => 10,
16 => 10,
17 => 10,
19 => 10,
21 => 10,
);
# the per node hop control thingy
%nodehops =
GB7ADX => { 11 => 8,
12 => 8,
16 => 8,
17 => 8,
19 => 8,
21 => 8,
},
GB7UDX => { 11 => 8,
12 => 8,
16 => 8,
17 => 8,
19 => 8,
21 => 8,
},
GB7BAA => {
11 => 5,
12 => 8,
16 => 8,
17 => 8,
19 => 8,
21 => 8,
},
};
Each set of hops is contained within a pair of curly braces and contains a series of PC frame types. PC11 for example is a DX spot. The figures here are not exhaustive but should give you a good idea of how the file works.
You can alter this file at any time, including whilst the cluster is running. If you alter the file during runtime, the command load/hops will bring your changes into effect.
It is possible to isolate networks from each other on a "gateway" node using the set/isolate <node_call> command.
The effect of this is to partition an isolated network completely from another node connected to your node. Your node will appear on and otherwise behave normally on every network to which you are connected, but data from an isolated network will not cross onto any other network or vice versa. However all the spot, announce and WWV traffic and personal messages will still be handled locally (because you are a real node on all connected networks), that is locally connected users will appear on all networks and will be able to access and receive information from all networks transparently. All routed messages will be sent as normal, so if a user on one network knows that you are a gateway for another network, he can still still send a talk/announce etc message via your node and it will be routed across.
The only limitation currently is that non-private messages cannot be passed down isolated links regardless of whether they are generated locally. This will change when the bulletin routing facility is added.
If you use isolate on a node connection you will continue to receive all information from the isolated partner, however you will not pass any information back to the isolated node. There are times when you would like to forward only spots across a link (maybe during a contest for example). To do this, isolate the node in the normal way and put in a filter in the /spider/filter/spots directory to override the isolate. This filter can be very simple and consists of just one line ....
$in = [
[ 1, 0, 'd', 0, 3] # The last figure (3) is the hop count
];